双向免疫扩散试验选择()
A.琼脂糖
B.琼脂糖珠4B
C.聚乙二醇
D.硫酸铵
E.聚丙烯酰胺
参考答案:A
解析:琼脂糖是双向免疫扩散试验中常用的支持物。
—What happened outside just now?
—A car hit a man. ______, the man wasn’t badly hurt.
A.Luckily
B.Hardly
C.Unluckily
D.Especially
These doctors are busy day and night, a cure for AIDS.
A.bringing on
B.pulling on
C.taking on
D.working on